scholarly journals Fabrication of Efficient and Selective Modified Graphene Paste Sensor for the Determination of Catechol and Hydroquinone

Surfaces ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 473-483
Author(s):  
Jamballi G. Manjunatha
Keyword(s):  
Modified Electrode ◽  
High Sensitivity ◽  
Differential Pulse ◽  
Official Method ◽  
Limit Of Quantification ◽  
Selective Determination ◽  
Graphene Paste Electrode ◽  
Modified Graphene ◽  
Paste Electrode

An electrochemical sensor, based on a graphene paste electrode (GPE), was modified with a polymerization method, and the electrochemical behavior of catechol (CC) and hydroquinone (HQ) was investigated using electroanalytical methods like cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The effect of CC at the modified electrode was evidenced by the positive shift of the oxidation peak potential of CC at the poly (rosaniline)-modified graphene paste electrode (PRAMGPE) and the nine-fold enhancement of the peak current, as compared to a bare graphene paste electrode (BGPE). The sensitivity of CC investigated by DPV was more sensitive than CV for the analysis of CC. The DPV method showed the two linear ranges of 2.0 × 10−6–1.0 × 10−5 M and 1.5 × 10−5–5 × 10−5 M. The detection limit and limit of quantification were determined to be 8.2 × 10−7 and 27.6 × 10−7 M, respectively. The obtained results were compared successfully with respect to those obtained using the official method. Moreover, this sensor is applied for the selective determination of CC in the presence of HQ. The high sensitivity, good reproducibility, and wide linear range make the modified electrode suitable for the determination of CC in real samples. The practical application of the sensor was demonstrated by determining the concentration of CC in water samples with acceptable recoveries (97.5–98%).

scholarly journals Poly (Adenine) Modified Graphene-Based Voltammetric Sensor for the Electrochemical Determination of Catechol, Hydroquinone and Resorcinol

2020 ◽  
Vol 14 (1) ◽  
pp. 52-62 ◽  
Author(s):  
Jamballi G. Manjunatha
Keyword(s):  
Differential Pulse ◽  
Electrochemical Determination ◽  
Repeatability And Reproducibility ◽  
Pulse Voltammetry ◽  
The Stability ◽  
Graphene Paste Electrode ◽  
Modified Graphene ◽  
Paste Electrode ◽  
Voltammetric Technique

Objective: This paper presents the application of Poly (Adenine) Modified Graphene Paste Electrode (PAMGPE) for the analysis of Catechol (CC) with Resorcinol (RC) and Hydroquinone (HQ) by a voltammetric technique. Methods: Electropolymerization technique was utilized for the modification of the sensor surface. The electrode surface was characterized by Field Emission Scanning Electron Microscopy (FE-SEM). Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) were used to study the redox behavior of CC, RC and HQ. Results: Oxidation peak current of CC increased linearly with the concentration of CC in the range from 2×10-6- 8×10-6 M and 1×10-5-1.5 ×10-4 M with a detection limit of 2.4×10-7 M. The practical application of the developed sensor was verified as exact for the determination of CC in water sample. Conclusion: The stability, repeatability, and reproducibility of the developed electrode were studied and established good characteristics. Furthermore, the PAMGPE was examined for the simultaneous determination of CC, RC and HQ.

scholarly journals Electrochemical Polymerised Graphene Paste Electrode and Application to Catechol Sensing

2019 ◽  
Vol 13 (1) ◽  
pp. 81-87 ◽  
Author(s):  
Jamballi G. Manjunatha
Keyword(s):  
Modified Electrode ◽  
Limit Of Detection ◽  
Phosphate Buffer Solution ◽  
Sample Pretreatment ◽  
Differential Pulse ◽  
Buffer Solution ◽  
Solution Ph ◽  
Graphene Paste Electrode ◽  
Paste Electrode

Objective: To build up an advantageous strategy for sensitive determination of catechol (CC), a poly (proline) modified graphene paste electrode (PPMGPE) was fabricated and used as a voltammetric sensor for the determination of CC. Methods: The performance of the modified electrode was studied using cyclic voltammetric (CV) and differential pulse voltammetric method (DPV). The modified electrode was characterized by CV and DPV. The surface of the modified electrode was examined by FESEM. The electrochemical behavior of CC in phosphate buffer solution (pH 7.5) was inspected using bare graphene paste electrode (BGPE) and PPMGPE. Results & Conclusion: The PPMGPE shows a lower limit of detection, calculated to be 8.7×10–7mol L−1 (S/N=3). This modified electrode was applied successfully for the determination of CC in water samples without applying any sample pretreatment.

scholarly journals Electrocatalytic determination of captopril using a carbon paste electrode modified with N-(ferrocenyl methylidene) fluorene-2-amine and graphene/ZnO nanocomposite

2019 ◽  
Vol 84 (2) ◽  
pp. 175-185 ◽  
Author(s):  
Mohadeseh Safaei ◽  
Hadi Beitollahi ◽  
Masoud Shishehbore ◽  
Somayeh Tajik ◽  
Rahman Hosseinzadeh
Keyword(s):  
Modified Electrode ◽  
Carbon Paste Electrode ◽  
Electrocatalytic Oxidation ◽  
Differential Pulse ◽  
Diagnostic Techniques ◽  
Carbon Paste ◽  
Pulse Voltammetry ◽  
Electrocatalytic Determination ◽  
Paste Electrode

A carbon paste electrode (CPE) was modified with N-(ferrocenylmethylidene) fluorene-2-amine and graphene/ZnO nanocomposite. The electrooxidation of captopril (CAP) at the surface of the modified electrode was studied using electrochemical approaches. The electrochemical study of the modified electrode, as well as its efficiency for the electrocatalytic oxidation of captopril, is described. The electrode was used to study the electrocatalytic oxidation of captopril, by cyclic voltammetry (CV), chronoamperometry (CHA) and differential pulse voltammetry (DPV) as diagnostic techniques. It has been found that the oxidation of captopril at the surface of modified electrode occurs at a potential of about 340 mV less positive than that of an unmodified CPE. DPV of captopril at the electrochemical sensor exhibited two linear dynamic ranges (0.1?100.0 and 100.0?800.0 ?M) with a detection limit (3?) of 0.05 ?M.

scholarly journals Selective Determination of Dopamine in Presence of Ascorbic Acid Using Nafion Coated Methylene Blue Functionalized Graphite Electrode

2019 ◽  
Vol 31 (10) ◽  
pp. 2185-2190
Author(s):  
G. Sivasankari ◽  
K. Sivasankari ◽  
T. Nalini ◽  
P. Padmapriya ◽  
M. Nadhiya
Keyword(s):  
Methylene Blue ◽  
Ascorbic Acid ◽  
Modified Electrode ◽  
Electrode Surface ◽  
Graphite Electrode ◽  
Low Cost ◽  
Differential Pulse ◽  
Selective Determination ◽  
The Stability

An electrochemical sensor has been developed using methylene blue (MB) unctionalized graphite for the selective determination of dopamine in the presence of ascorbic acid. The immobilization of methylene blue on graphite was done by carbodiimide coupling method. The methylene blue functionalized graphite was characterized by SEM, FTIR spectroscopy and UV-visible spectroscopy. The immobilization of methylene blue functionalized graphite (MB-G) on the electrode surface was made by drop casting a small volume of MB-G dispersed methanol solution on the electrode surface. About 5 L of 0.5 % Nafion solution was also dropcasted for the stability and selectivity. The MB-G modified electrode was characterized by cyclic voltammetry. The modified electrode promotes the electrocatalytic oxidation of dopamine at a lower potential of 160 mV. The selective determination of dopamine in the presence of 100 times higher concentration of ascorbic acid was achieved by differential pulse voltammetry. The modified electrode offered a simple, selective and sensitive determination of low levels of dopamine. Also the oxidation over potential was reduced to an extent of 360 mV comparing with the bare graphite electrode. The proposed sensor has the advantage of easy fabrication, low cost, good sensitivity, reproducibility and stability.

scholarly journals A novel dopamine electrochemical sensor based on La3+/ZnO nanoflower modified graphite screen printed electrode

2019 ◽  
Vol 9 (3) ◽  
pp. 187-195 ◽  
Author(s):  
Somayeh Tajik ◽  
Hadi Beitollahi ◽  
Mohammad Reza Aflatoonian
Keyword(s):  
Modified Electrode ◽  
Phosphate Buffer Solution ◽  
High Sensitivity ◽  
Differential Pulse ◽  
Electrochemical Determination ◽  
Screen Printed Electrode ◽  
Buffer Solution ◽  
Optimized Conditions ◽  
Screen Printed

Flower-like La3+/ZnO nanocomposite was facile synthesized. A simple and ultrasensitive sensor based on graphite screen printed electrode (SPE) modified by La3+/ZnO nanoflower was developed for the electrochemical determination of dopamine. The electrochemical behavior of dopamine was studied in 0.1 M phosphate buffer solution (PBS) using cyclic voltammetry (CV), chronoamperometry (CA) and differential pulse voltammetry (DPV). Compared with the unmodified graphite screen printed electrode, the modified electrode facilitates the electron transfer of dopamine, since it notably increases the oxidation peak current of dopamine. Also, according to CV results the maximum oxidation of dopamine on La3+/ZnO/SPE occurs at 150 mV which is about 140 mV more negative compared with unmodified SPE. Under optimized conditions, the modified electrode exhibited a linear response over the concentration range from 0.15 to 300.0 μM, with a detection limit of 0.08 μM (S/N = 3). The proposed sensor exhibited a high sensitivity, good stability and was successfully applied for dopamine determination in dopamine ampoule, with high recovery.

scholarly journals Carbon nanotube-ionic liquid nanocomposite modified carbon-ceramic electrode for determination of dopamine in real samples

2013 ◽  
Vol 11 (7) ◽  
pp. 1172-1186 ◽  
Author(s):  
Mir Majidi ◽  
Reza Baj ◽  
Abdolhossein Naseri
Keyword(s):  
Ionic Liquid ◽  
Carbon Nanotube ◽  
Modified Electrode ◽  
Electrochemical Impedance ◽  
Differential Pulse ◽  
Selective Determination ◽  
Carbon Ceramic Electrode ◽  
Electro Oxidation ◽  
Carbon Ceramic

AbstractRoom temperature 1-butyl-3-methylimidazolium tetraflouroborate ([BMIM][BF4]) ionic liquid was employed for dispersion of multi walled carbon nanotubes (MWCNTs) and the formation of nanocomposite on the surface of a carbon-ceramic electrode. The surface of the modified electrode was characterized using scanning electron microscopy and electrochemical impedance spectroscopy. The modified electrode exhibited excellent electrochemical activity to oxidation of dopamine (DA); whereas electro oxidation of ascorbic acid (AA) was not seen and electro oxidation of uric acid (UA) appeared at a more positive potential than DA. The multi walled carbon nanotube-ionic liquid nanocomposite modified carbon-ceramic electrode was used for the selective determination of DA in the presence of high levels of AA and UA using differential pulse voltammetry. The calibration curve for DA was linear in the range of 3.00 to 130 µM with the detection limit (S/N=3) of 0.87 µM. The present electrode was successfully applied to the determination of DA in some commercial pharmaceutical samples and human blood serum.

scholarly journals Development of a Carbon Paste Electrode Containing Benzo-15-Crown-5 for Trace Determination of the Uranyl Ion by Using a Voltammetric Technique

2009 ◽  
Vol 92 (1) ◽  
pp. 241-247 ◽  
Author(s):  
Sunil K Agrahari ◽  
Sangita D Kumar ◽  
Ashwini K Srivastava
Keyword(s):  
Detection Limit ◽  
Differential Pulse Voltammetry ◽  
Modified Electrode ◽  
Carbon Paste Electrode ◽  
Electrochemical Impedance ◽  
Differential Pulse ◽  
Carbon Paste ◽  
Pulse Voltammetry ◽  
Paste Electrode

Abstract The interaction of macrocyclic compounds like crown ethers and UO22+ has been studied by electrochemical methods. A modified carbon paste electrode incorporating benzo-15-crown-5 (B15C5) was used to evaluate the electron transfer reaction of UO22+ by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Electrochemical impedance studies showed that charge transfer resistance was less for the B15C5-modified electrode than for the plain carbon paste electrode (PCPE). On the basis of these observations, a UO22+-sensitive crown ether chemically modified electrode (CME) for trace analysis was fabricated and investigated in aqueous solutions. It was found that a 5 B15C5CME for UO22+ showed a better voltammetric response than did the PCPE. UO22+ could be quantified at sub-μg/mL levels by differential pulse voltammetry with a detection limit of 0.03 μg/mL. By differential pulse adsorptive stripping voltammetry, UO22+ could be quantified in the working range of 0.002-0.2 μg/mL, with a detection limit of 1.1 μg/L. Simultaneous determination of UO22+, Pb2+, and Cd2+ was possible. The method was successfully applied to the determination of UO22+ in synthetic, as well as real, samples; the results were found to be comparable to those obtained by inductively coupled plasma-atomic emission spectroscopy.

scholarly journals Development of a Method for a Sensitive Simultaneous Determination of Dopamine and Paracetamol in Biological Samples and Pharmaceutical Preparations

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Ali Babaei ◽  
Aliyeh Dehdashti ◽  
Mohammad Afrasiabi
Keyword(s):  
Detection Limit ◽  
Modified Electrode ◽  
Pharmaceutical Preparation ◽  
Pharmaceutical Preparations ◽  
High Sensitivity ◽  
Differential Pulse ◽  
Linear Range ◽  
Multiwalled Carbon ◽  
Excellent Stability

A chemically modified electrode is constructed based on multiwalled carbon nanotube—modified glassy carbon electrode (MWCNTs/GCE). The measurements were carried out by application of differential pulse voltammetry (DPV), cyclic voltammetry (CV), and chronoamperometry (CA) methods. Application of DPV method showed wide linear range of DA from 1 μM to 540 μM and a detection limit of 0.098 μM (S/N=3). The linear range of PAR of 3 μM to 300 μM and a detection limit of 0.15 μM, were obtained. The modified electrode showed electrochemical responses with high sensitivity, high selectivity, and excellent stability for DA and PAR determination at optimal conditions, which makes it a suitable sensor for simultaneous submicromolar detection of DA and PAR in solutions. The analytical performance of this sensor has been evaluated for detection of DA and PAR in human serum, human urine, and pharmaceutical preparation with satisfactory results.

Sign in / Sign up

Export Citation Format

Share Document